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24 maj 2014

Since the severe criticism of Lennart Bengtsson from some of us at Uppsalainitiativet in the last few weeks (post 1, post 2, post 3) had begun to attract some international interest (see, e.g., Eli Rabett's translation of post 1), we felt it would be a good service to the international community to publish an English translation of Bengtsson's response to us. We imagined that the many glaring shortcomings of his rambling arguments and the untenability of his position would be evident and speak for themselves, but judging from the number of enthusiastic supporters of Bengtsson's text that showed up in the comments section, it seems that some clarification is needed. We already stated, in the brief introduction to the translation, that "our translation and publication of this text in no way means that we endorse the views expressed in it". Stronger language than that is warranted, and let me state it bluntly: much of what Bengtsson writes in his blog post goes right against our blog's subtitle "TAR KLIMATVETENSKAPEN PÅ ALLVAR", which in English reads "TAKES CLIMATE SCIENCE SERIOUSLY".

1) Anthropogenic climate change has increased several types of extreme weather, particularly heat waves, and is projected to intensify many others, for example drought intensity. http://www.skepticalscience.com/extreme-weather-global-warming-intermediate.htm

Exactly so. Here's that link again. The fact (pointed out by an anonymous commentator further down) that the IPCC mentions ambiguities and the inconclusive state-of-the-art concerning specific kinds of extreme weather does not warrant misleading statements like Bengtsson's"Apart from a possible increase in precipitation and a possible intensification of tropical hurricanes that has not yet been detected, there are no indications of extreme weather in the model simulations, and even less so in current observations".

2) There seems to be some confusion about the ability to model the future perfectly vs. the ability to project a distribution of probable future climate changes. Prof. Bengtsson seems to argue that if we can't project future climate change perfectly then we can't project it at all (the chaos theory comments). In reality it's simple physics that if we continue to increase the greenhouse effect and global energy imbalance, that will cause hotter temperatures and 'load the dice' in favor of certain associated climate changes (stronger heat waves, droughts, intense precipitation, etc.).

Exactly. And let me add to this the ambiguity that Bengtsson plays with when he says that"climate cannot be predicted, and how future climate will turn out will not be known until future is upon us". Here he could mean either (a) the utterly trivial and uncontroversial fact (exemplified by IPCC:s broad "likely" range of 1.5 to 4.5°C for the value of climate sensitivity) that we cannot predict the exact future climate, or (b) the blatant falsehood that we cannot know anything about where the climate is heading, or (c) something in between these two extremes, in which case he needs to explain his position with a lot more precision than the empty rhetoric presented in his guest post.

3) Temperatures over the oceans are not representative of the warming of the planet as a whole.

Right. The kind of cherry picking that Bengtsson engages in with his statement that "the long period during the last 17 years with insignificant or no warming over the oceans" is unworthy of serious scientific discussion.

4) There is substantial research into the cause of the slight increase in Antarctic sea ice extent, which is happening in a region with warming temperatures.

5) If you still don't understand why your colleagues were upset that you joined GWPF, you need to spend more time looking into the comments and reports made by the group, for example about the IPCC and Michael Mann.

Yes. All it takes is a quick tour through the GWPF web site to see that they are an anti-scientific climate denialist organisation. The dismay expressed by Bengtsson's critics upon his joining the GWPF is amply justified, and analogous to what a well-known evolutionary biologist would surely hear from his colleagues in case he suddenly decided to join the Discovery Institute or some other creationist think tank.

That concludes Nuccitelli's list, but there is more. Let me just add two more items.

6) Bengtsson speculates on how "prominent Jewish scientists in the GWPF council [feel about] being labeled deniers". I am dismayed by his choice to bring ethnicity issues into this discussion, and I feel almost embarrassed to point out that "denier" and "Holocaust denier" are not synonymous concepts. Climate denialists like to conflate the two terms, usually in an attempt to change the subject of a conversation, and I am sad to see how Bengtsson chooses to resort to the same lousy trick.

7) Bengtsson resorts to Popperian falsificationism in branding findings to the extent that "even extremely cold weather, as this year’s winter in north Eastern USA and Canada, is regarded as a consequence of the greenhouse effect" as "pseudo-science". I refuse to lecture to Bengtsson about the many complexities and nonlinearities of the climate systems, leading to geographic inhomogeneity of global warming and various conuterintuitive phenomena; surely Bengtsson knows about these things (and probably a lot more than me, for that matter). The Wikipedia entry on last winter's cold spell in North America has a section on the possible role of anthropogenic climate change, containing plenty of references. The blank dismissal of such work as "pseudo-science" is just rude and anti-intellectual. Elsewhere, Bengtsson gives the same treatment to studies of melting in Antarctica (such as the recent one by Eric Rignot et al), recommending that they are not read but sent straight to the waste basket. Such dismissal of scientific work, based not on their methodology but on their uncomfortable results, is characteristic of climate denial, and it is just terrible to see how far in that direction Bengtsson has gone in recent years.

It is not uncommon, but always annoying, to hear people with apparently a very crude understanding of the theory of science point to Popperian falsificationism to label one study or another (or sometimes entire subjects) as "pseudo-science". A study does not become pseudo-scientific just because it fails to falsify some theory. If Bengtsson's invokement of Popper is to be taken seriously, then we would equally well have to rule out as "pseudo-science"the mid-1800's study of anomalies in the orbit of Uranus, because it led to the discovery of Neptune rather than the falsification of Newton's theory of gravity.

33 kommentarer:

Regarding the extreme weather events, lets assume one accepts Bengtsson's very high requirements on evidence. Then it is easy to see that in a climate changing world with a gradual increase in frequency of events emerging from the weather noise, there will be a real increase long before he accepts that it happens, i.e. he will be wrong during some time (in the real world that is very likely where we are now). But to prepare properly you would rather need to act before things happen. A Bayesian framing is probably a good way to be more realistic where you interpret observations against some physical a priori model of what to expect. I think this is one of the main weaknesses in his entire attitude of "wait and see until we know better" and it is part of the ESLD effect which causes a bias (but not a political one) in assessments. Bengtsson seems to be a proponent for an unusually strong ESLD attitude, which might not be well suited for when you push a complex system. But of course, if you value the prestige of the climatologists more than the potential victims of climate change this is rational (kind of), you might be (very) wrong if you assert something, even if it is optimally derived from available evidence.

The second big issue I think is the ethics. Aside that Bengtsson does not seem to value the rights of the unborn generations too much, his behaviour has been seriously lacking in this entire affair (e.g. see this and previous blog posts). To keep the comment short, I'd just say the climate debate need more young female moral philosophers and fewer Bengtssons.

"I'd just say the climate debate need more young female moral philosophers and fewer Bengtssons."

This is so sad! Why should it matter what age or gender the messenger has? And moral philosophers? If anything, moral must be left out of climate science if it ever is to get a broad acceptance. Moral implies opinion and you can never be an expert in opinion.

"there will be a real increase long before he accepts that it happens, i.e. he will be wrong during some time (in the real world that is very likely where we are now)"

Likewise those who argue that it should already have happened have been wrong so far in a scientific view as a trend that stands out of the noise has not been proven yet. Of course it might be dangerous to wait and see but some argue that taking action with improper evidence is also dangerous (like a doctor ordering treatment when being unsure of the diagnose).

"Or like a doctor refusing to order treatment of symptons - despite a fairly good diagnosis - until the patient is dead and a necropsy can be perfomed."

Would you say the symptoms are obvious today, for instance regarding extreme weather events?

Would you agree that what authority tells us thus far (IPCC) is that there is low confidence in such events being present today? They then need to be linked to a cause (where CO2 are partly responsible for warming since 1950, again according to IPCC). Of corse you know all this and so does LB. Probably a large portion of the knowledge we have in this field today originates from LB via AR3. Your analogy with the patient being dead is therefore somewhat faulty I would say.

I would say that the symptoms today are not contradictory to the disease. They are, however, in alignment with predicted symptoms even if not statistically certain, and there is good cause to suspect they will worsen. Further, the patient IS evidently running a fever.

This is interesting. Whom would you see as best suited to assess:1) If there are any symptoms?2) How to define fever in this case?

It is of corse impossible to challenge that the symptoms are contradictory to the disease if the symptoms are not statistically certain. If there are no spots on the tongue, it is hard to prove that it is not measles... Also, not statistically proven symptoms are still harmless if they are worsened. If there are no certain trend, amplifying it will not make it worse. Did I read your post wrong here?

"It is of corse impossible to challenge that the symptoms are contradictory to the disease if the symptoms are not statistically certain."

A trend can be flat, point the wrong way or the right way. If it is flat, or points the wrong way, then yeah, most likely the hypothesis is not waterproof - or you have an error in your methods. But in the case it points the way you would hypothize that it does but the trend does not fall outside of what can (theoretically) be due to randomness, then all the trend does is to be unable to disprove the null hypothesis.Now, and this is a very common mistake, I have even seen other scientists do it, they say that the hypothesis is disproven, or even worse that the null hypothesis is proven if the trend is not statistically significant. But that is not what it means at all. What it means is that we should get more data points, to make sure the trend was not due to chance.

However, in most science, you do not gamble with the future of humankind. This is where the political interpretation comes in."We found a trend concurrent with our hypothesis, that is derived from a proven hypothesis, but we could not prove that it was beyond 5% likelyhood due to chance. But if we are right, mankind is slightly more fucked than it would be anyways unless we stop carbon emissions."It is of course up to every individual to do their own political interpretation from this. Needless to say, I do not share Bengtssons patience. Especially since even without hurricanes etc we will suffer from higher temperatures, mostly from water shortage, destruction of biotopes and inexperience with extreme heat (for instance, 5000 people died in France because they for 3 days got the same temperature that... err... Saudi Arabia (?) have all year).

Now, I do not at all understand physics, but I do know that the Higgs-Boson was in much the same way predicted as hurricanes etc. Their attitude was "We know it is there, we just have not proven it yet". Somehow, this did not attract the attention of the oh-so-concerned-with-Karl-Popper-just-ordinary-citizens crowd.

"Whom would you see as best suited to assess"

It is not a who, it is an it, and the it is called the scientific method. Scientific arguments are strong not because of who makes them, but because the soundness of the methods and the reasoning. An a priori assumption would be that a professor is more experienced and knowledgeable of methods and more skilled with reasoning than a master student. That is, however, not always the case.

"Scientific arguments are strong not because of who makes them, but because the soundness of the methods and the reasoning."

Spoken like a hardcore sceptic! Personally I have a hard time getting this philosophy to work well in daily life. You're saying, I personally would have to evaluate an absurd amount of arguments in all kinds of scientific fields. I would not be a happy person doing nothing but reading books and reports. That is why it is sound to rely on authority freeing up time for me to be with my family? I have been very thankful for the IPCC summaries thus far, since I will then not have to spend the 5+ years to be able to make a somewhat well-based assessment of climate change. Now you're telling me that I cannot do this way? Well sir, I think you are wrong and I will continue to take advice from those considered authority over people with home made hypothesis on blogs.

No, that is not at all what I am saying. Of course I too rely on "authority" - if you want to call it that - for arguments which are not within the scope of my field of expertise. And inside my field of expertise as well, I should add.

What I am saying is that scientific understanding is not a battle of merits. The argument I detect behind the argument you just made is that if LB makes a claim, by virtue of being a renown professor, it is equally valid to an argument made by any one other climate professor. Thus, if even one professor disagree with mainstream science, that entire field is put into limbo, where all claims, regardless of how dumb, are equally valid, until "the science has settled".

This is the method by which the authority argument legitimize all manner of denialist drivel, if you buy into it.

I'd rather put it this way, Lars: The reason that we tend to trust the scientific community is that we have good reasons to believe that they came to their conclusions using the scientific method. The reason that we tend to trust individual scientists in their field of expertise is not that they came to their conclusions using the scientific method (hardly any individual scientist has personally contributed more than a fraction of a percent of the knowledge in their field), but that they have sufficiently well-informed insight into this process to be able to make sound judgements about what is known in their field.

It is also important to realize that individual scientists are mere humans, and that humans sometimes show poor judgement, in which case we have reason not to trust them.

In general, I'd say that an organization like the IPCC, with its layers of peer review, is more trustworthy than an individual scientist. If the organization should happen to contain one or more individuals lacking in judgement, the mistakes of those individuals can be corrected by their peers.

"It is also important to realize that individual scientists are mere humans, and that humans sometimes show poor judgement, in which case we have reason not to trust them."

This is a circular argument Olle H! Whom should I trust when deciding whether or not these individuals have poor judgement?

"In general, I'd say that an organization like the IPCC, with its layers of peer review, is more trustworthy than an individual scientist."

Agreed! Therefore, since I haven't seen any statement from the IPCC regarding Bengtssons media drive, I will await such a statement before listing him as a serious researcher. I may dislike what he is saying but I must still consider him authority.

"If the organization should happen to contain one or more individuals lacking in judgement, the mistakes of those individuals can be corrected by their peers."

This is true, but I haven't seen that many of LBs peers backing statements mad by the staff from Uppsala Initiativet? Please help me out if I have missed this. His research fellow Hans von Storch is supporting LB (to some extent) in a comment on this blog and even though there are other peers whom seem to think he has acted inappropriate, it cannot be concluded that either side is in majority. Note that from the comments on this blog I find almost only HvS being among LBs peers, but please correct me if I'm wrong.

@Olle H:Thank you for the thorough answer. Most of the items you list seem to adress non-scientific/political arguments extracted from a debate? I'm not taking the time to read them all now but can agree that they seem to belong more in a political debate than a scientific one. Still this doesn't necessarily mean that LB has lost his scientific judgement and should therefore no longer be considered an authority when it comes to climate science.

(d) seems of corse to be several nodges below what can be expected from a scientist but I would assume his peers would withdraw their support if such claims had been made as bluntly as you put them.

I don't prioritize the time to make own assessments of the judgement of climate authorities. What club memberships lead authors of IPCC have is not my concern. Even if they were to be members of the big coal lobby I could still consider them authorities if they were cited in IPCC reports. I think your reasoning opens the door to a political assessment of whom I should view as authority and that can never be a good thing.

Anonymous 13:56/16:34. I chose non-scientific issues on my list, because I got the impression you were a nonexpert, not able to judge the science itself. If you now rule out non-scientific issues as irrelevant to judging a scientists' trustworthiness in communicating science (I don't think it always is, but of course you're free to take that stand), then it seems you have no tool at all for judging that. Fine. I would still recommend (based on the distinction the scientific community vs individual scientists that I made above (10:09)) that you put more trust in the scientific community's overall consensus view (as summarized in the IPCC report) than in individual contrarians.

You're right. I don't have a tool for evaluating the judgement of those considered authorities in scientific questions. Even though a person is diagnosed mentally ill, they can still be astonishing scientists (the movie "A beutiful mind" is acutally based on a true story).

I definitely agree on what you say about the scientific community vs individuals. In this case, however, it seems like LB has support from at least parts of the community whereas opposition has come mostly from other stakeholders (i.e. not scientific experts). I think this is in perfect order and it's good to raise awareness if LB is changing to a contrarian, but it doesn't mean he can no longer serve as a scientific authority.

There is no such thing as a "scientific authority". That is simply just NOT how science works. I can not for the life of me imagine a group meeting where sound ideas are thrown out because "Authority A says our proposal is impossible" or something similar. Again, that is simply just not how it is done. Sound ideas, even if proposed by the janitor, WILL BE RIGOROUSLY TESTED (provided the group hasnt already spent their funding)!!! And I dare say even the most imposing professor will be ripped apart by his/her OWN students, if he sticks to an idea sufficiently disproven or an idea that is based on overenthusiastic interpretation of avaible evidence (although the ripping will be done in a patient and respectful way).

Do you even understand what empiricism means?"Empiricism in the philosophy of science emphasizes evidence, especially as discovered in experiments. It is a fundamental part of the scientific method that all hypotheses and theories must be tested against observations of the natural world rather than resting solely on a priori reasoning, intuition, or revelation."http://en.wikipedia.org/wiki/Empiricism

And let me preventively explain that "observation" in this instance also includes models and predictions, much in the same way physicists had a "faith-based" belief in the Higgs-Boson. Such "observation" are later overwritten by actual observations in case there is a mismatch. Also please note there is currently no mismatch between climate models and predictions and actual observations, such as pretended by Bengtsson, what with the nonsense about the hiatus and how we dont have enough hurricanes etc (yet).

"Authority" in science simply means that we do not distrust all articles off the bat until we repeat the experiment itself, and that we put higher degree of trust in an article in science than in an article in... uhhh... annals of homepathy.

"Sound ideas, even if proposed by the janitor, WILL BE RIGOROUSLY TESTED"

"we put higher degree of trust in an article in science than in an article in... uhhh... annals of homepathy"

If you argue that you consider articles in scientific journals similar to scientific authorities then I can agree with you. That is what I've been saying for a while now.

However, I've been through this debate several times but almost exclusively on sceptical blogs. Have you tried them out? They seem to be right up your alley, at least the first part of your post.

On sceptical blogs, everyones word is equally evaluated and authority is of no relevance. This way of reasoning is of little or no help to me and I see it as useless in everyday life. When I fell sick, I'll go to the doctor instead of trying to ask for diagnosis in internet forums and evaluating them one by one. Perhaps you choose to award your doctor the same credibility as the school janitor? I then use this approach to many scientific fields since I could never learn enough to be able to evaluate them all.

With this reasoning, I can simply dismiss your paragraph that the hiatus doesn't exist and that there are no mismatch between models and reality. The IPCC is authority is this regard whereas you are not (that I know)! The IPCCs leading scientists are currently is studying the hiatus in order to better understand why the models have diverged from measured temperatures in recent years! It would take a hardcore anti-scientist to be able to say the hiatus is not a reality. The hiatus by no way disproves the threat from climate change but saying it doesn't exist would be to discredit our finest scientists like Kevin Trenberth whom has been investigating the phenomena for years now.

Making models that predicts temperatures is perhaps the most challenging task mankind has set out to do thus far. Wouldn't it be strange if we got it all right immediatly from start? Now we have several models that have been working quite well but trying to ignore the discrepancy between measurements and predictions is perhaps the most foolish thing that can be done. How are we ever to improve the models with such an approach?

"Sound ideas, even if proposed by the janitor, WILL BE RIGOROUSLY TESTED"

"we put higher degree of trust in an article in science than in an article in... uhhh... annals of homepathy""

How is that a contradiction?

"If you argue that you consider articles in scientific journals similar to scientific authorities then I can agree with you. That is what I've been saying for a while now."

No, you have been saying that LB is a scientific authority, thus showing ignorance of how the scientfific living discussion works. Even journals are not authorities in the way you understand it. There is no blind trust in science, everything is under scrutiny.

"Making models that predicts temperatures is perhaps the most challenging task mankind has set out to do thus far."

No. It is certainly not more difficult than landing on the moon, yet we did that.

"Perhaps you choose to award your doctor the same credibility as the school janitor?"

You understand, of course, that western medicine is evidence-based, and a doctor who refuse the most relevant treatment because it was initially proposed by a janitor might get his/her license suspended.

"The IPCCs leading scientists are currently is studying the hiatus in order to better understand why the models have diverged from measured temperatures in recent years!"

I am sure you are exaggerating. Of course you always discuss discrepancies and their causes. However, do IPCC-AR5 state that the discrepancies are such that the entire field of climate change is put into serious doubt? Yes/No question for you.

"It would take a hardcore anti-scientist to be able to say the hiatus is not a reality."

Or this guy;https://www.youtube.com/watch?v=W705cOtOHJ4

"However, I've been through this debate several times but almost exclusively on sceptical blogs. Have you tried them out? They seem to be right up your alley, at least the first part of your post."

I have read some of their posts, yes. Some of it is even very convincing due to its elegant rhetorics, even if most is sluggish. I find that the elegant ones are... how do you put this? Like, getting hit in the solar plexus. At first you are stunned, but then you quickly start to recover. Roughly halfway through I begin to spot all the fallacies, half-truths and misrepresentations of facts. But I can easily see how even intelligent people can be perplexed by them.

"Now we have several models that have been working quite well but trying to ignore the discrepancy between measurements and predictions is perhaps the most foolish thing that can be done."

Speaking of contradicting yourself, why do I need to listen specifically to an "scientific authority" such as LB if mainstream climate science also agree that warming have stopped and all models are worthless?

"However, do IPCC-AR5 state that the discrepancies are such that the entire field of climate change is put into serious doubt? Yes/No question for you."

No absolutely not! I hope I haven't implied something as horrible as this in my post above? To be clear: the research field of climate is vital to the evolution/well being of mankind and is important under all circumstances (even if the IPCC would for some reason consider climate sensitivity low). You were saying though:

"Also please note there is currently no mismatch between climate models and predictions and actual observations, such as pretended by Bengtsson, what with the nonsense about the hiatus and how we don't have enough hurricanes etc (yet)."

Now this is in sharp contrast with what authority is saying! The AR5 is discussing the hiatus (wasn't it even the IPCC which picked up the phrase "hiatus" in the first place?) and is closely following on the latest research on this theme. If there were no hiatus, like what you're saying, then the IPCC would surely not focus that much energy on studying the phenomena. The hiatus does by no means eliminate the threat from rising temperatures or climate change.

"why do I need to listen specifically to an "scientific authority" such as LB if mainstream climate science also agree that warming have stopped and all models are worthless?"

You mix up two items. Warming has slowed compared to the (sometimes alarming) rapid growth during the later part of the 20th century. Arguing against this fact is just sad and I haven't seen anything like this originating from the IPCC or what can be considered authorities on climate.

Models have shown a discrepancy compared to measured temperatures but this is absolutely not the same thing as saying the models are worthless! Actually, if the models had been spot on in their prediction, then they would surely (!!) have been meaningless since the research frontier still are inconclusive about a lot of the variables (like clouds for instance)! If the models were precise and we still didn't know all the variables, it would be worse than having a discrepancy like we have now.

You do have a point that an individual is less of a authority than a wider group such as the scientific community (if that was your point). However, it is more practical if you can also appoint a few leading individuals within the scientific community as authorities by them selves. Of corse there is always a possibility that a janitor can say something relevant about whether that Trenberth have overlooked but providing them equal room in a debate is just a waste of time. You can do it if you want but I prefer to listen to authority instead of your home made theories that there is no hiatus and that the models are spot on. This is the part sceptics never agree upon.

If LBs views are in line with IPCCs can be questioned, but I prefer waiting for some kind of statement from the scientific community before dismissing him as authority in regards of meteorology due to his earlier commitment as lead author in ARs.

"The hiatus does by no means eliminate the threat from rising temperatures or climate change."

There, you did it again! You phrase the the hiatus in such a weasel way that it may be interpret as if global warming have stopped while it can also be interpret as if you agree with mainstream science.

So why do I not ask you outright;1. Have global warming stopped in your opionon?2. Have IPCC claimed global warming have stopped in your opionon?

"that there is no hiatus and that the models are spot on"

Of course, this what I actually said;

"I would say that the symptoms today are not contradictory to the disease. They are, however, in alignment with predicted symptoms even if not statistically certain, and there is good cause to suspect they will worsen."

My impression is that the current temperatures are within error bars;http://www.skepticalscience.com/Climate-Models-Show-Remarkable-Agreement-with-Recent-Surface-Warming.html

The problem I have with the word "hiatus" is that it means "pause". Now, a pause is something that may be resumed later rather than a stop. But I still do not like the word. Because there is no pause. It is just natural forcings conspiring to make the weather stable for 17 years, which gives the appearence of a pause, but it is not an actual pause.

"You do have a point that an individual is less of a authority than a wider group such as the scientific community (if that was your point)."

But would you stop nagging about authorities??? No, that was not my point. This is my point;"There is no such thing as a "scientific authority". That is simply just NOT how science works.""Do you even understand what empiricism means?"

Now, I can add that orthodox empiricism is not the same as scientific empiricism, and empiricism is just one of many underlying philosophies that bind together the scientific method.With that said, why do I nag about empericism? Because;"Scientific theories are judged by the coherence they lend to our natural experience and the simplicity with which they do so. The grand principle of the heavens balances on the razor's edge of truth."

A "scientific authorithy" is REJECTED when he/she/it forgo the scientific method. Speaking of LB...

Last attempt on my behalf since we have started to repeat arguments without making much progress.

"So why do I not ask you outright;1. Have global warming stopped in your opionon?"

What I've been trying to say is that mine, yours and the schools janitors opinion is equally meaningless in this regard. I've followed the debate for more than 10 years but still I know I couldn't last a full minutes discussion with a professional climate scientist. Therefore my opinion is irrelevant! My opinion matters whn it comes to preferences like which color is nicest but it is irrelevant in matters of science. When it comes to climate science, simply accepting what authorities say is the best I can do unless I spend my life on becoming a climatologist myself.

"2. Have IPCC claimed global warming have stopped in your opionon?"

Not stopped, but IPCC has claimed there are, for a specific (cherry picked if you will) period, no significant warming. Again, this is not even controversial since a few years now and it is also not a proof of anything. It is something that is worth studying and it is an opportunity to learn more about the climate system.

In my view, you meet all requirements of troll on a sceptical blog. First there's the home made hypothesis ('there is no pause its just natural forcings...' etc.), then there is the own bias when not agreeing with the scientific community ('I dont like the word hiatus because'...) and then a reference to a blog that 'your side' is proposing (in this case skepticalscience). Now look at the above sentence and switch SkSc for wuwt and maybe you'll find you're not that far away from the reasoning of a sceptic?

Nisse: "Bengtsson seems to be a proponent for an unusually strong ESLD attitude, which might not be well suited for when you push a complex system."

This is another core issue. Bengtsson writes that "As a result of chaos theory, weather and climate cannot be predicted, and how future climate will turn out will not be known until future is upon us."

We (and the rest of the biosphere) are very much dependent on the climate, and yet we are messing with it by adding large amounts of greenhouse gasses to the atmosphere. We cannot control the climate, but we are clumsily and inadvertently affecting it. That is a very dangerous thing to do with a complex system that has chaotic aspects.

But of course, the "us" in "until future is upon us" is not really us not-so-young people, but those who are young or not even born yet. It is always easier to take risks with other people's welfare than with your own, but it is not very ethical.

I agree very much. And the "system" includes things as ecosystems, human societies etc.At risk management courses you are taught the heuristic principle of first trying to remove the conditions for the dangerous to occur, rather than entering the complexities of trying to adapt and protect yourself against it. It applies more the more complex and dangerous problem.

Also, if you only rely on explicit well-proven scientific results for judging the future impacts there is a risk of underestimation because the surprises and future added knowledge are about changes to what you are adapted to, which naturally in most cases means something costly.

Bengtsson argues more like a business lawyer (i.e. typical "climate skeptic"). As long as there is no strong explicit evidence for bad impacts, we don't have to do anything (or rather, "we" will get more money and get away with it by saying so...) .

Table 2.13 shows that there has been a likely increasing trend in the frequency of heatwaves since the middle of the 20th century in Europe and Australia and across much of Asia where there are sufficient data. However, confidence on a global scale is medium owing to lack of studies over Africa and South America...

further analyses continue to support the AR4 and SREX conclusions that it is likely that since 1951 there have been statistically significant increases in the number of heavy precipitation events in more regions than there have been statistically significant decreases

For each different area it is of course also interesting to know what is happening there and not only globally. We of course also think it is good if one sees faults in media reporting and try to correct that.

1) Som du har påpekat: "I accept that Environmental Research Letters is entitled to its final decision not to publish this paper – that is part and parcel of academic life. The peer review process is imperfect but it is still the best way to assess academic work."Varför förväntar du då dig att vi skall göra någon slags granskning av artikeln. Har du inte accepterat deras beslut i alla fall?

A quotation from Anders Bolling in a blog post in Dagens Nyheter:http://blogg.dn.se/framstegsbloggen/2014/05/30/icke-trender-och-grupptryck/#comments

Lennart Bengtsson has testified that he also received plenty of support from academics in the UK, Germany and the United States because he takes care to balance the climate picture. Typically, they don't show this openly. In Sweden there are meteorologists who are worried about how Bengtsson is treated and the state of the debate. I know, because I have had such contacts. Do even these meteorologists want to remain anonymous? Have Antarctica thick ice? To explain one of them states: "Peer pressure is huge, and it's easy to be regarded as imbecile even though it really only deals with scientific critical thinking. If a giant like Lennart Bengtsson gets into trouble, it hardly encourages others to make their voices heard. "